Inking mechanism



Dec. 30, 1958 c. A. HARLESS 2,866,410

INKING MECHANISM Filed Feb. 27. 1952 IN VEN TOR.

(7 44 9455 fl. fiA/PZES United States Patent Office 2,866,410 PatentedDec. 30, 1958 INKING MECHANISM Charles A. Harless, Riverside, Conn.,assignor to R. Hoe &

C0., Inc, New York, N. Y., a corporation of New York This inventionrelates to improvements in inking mechanisms.

More particularly, the invention is concerned with inking mechanisms ofthe type in which ink is supplied to a plate or printing cylinder byform rollers which, in turn, are supplied with ink by trains of rollersor cylinders, which spread and work the ink progressively for supplyinga uniform film.

In such mechanisms, there is a tendency when a gap or gutter between theplate passes a form roller, to cause vibration and jumping, this beingobviously undesirable, and tending to produce uneveness and streaking inthe printing. It is an object of the invention to provide an improvedarrangement of rollers for minimizing the radial vibration and the speedvariation of the form rollers.

There is also a tendency in inking mechanisms of the character indicatedfor solid areas on a printing plate to remove most of the ink from largeareas on the form rollers, and produce sparse printing or ghosts inareas following. The invention contemplates also an improved arrangementof rollers for minimizing this effect.

An inking mechanism embodying the invention in a preferred form will nowbe described with reference to the accompanying drawing, and thefeatures forming the invention will then be pointed out in the appendedclaims.

The drawing is a schematic end elevation view of a printing mechanismembodying the invention in a preferred form.

There is indicated a relief plate or printing cylinder 1 cooperatingwith an impression cylinder 2 for printing on a web 3. The invention isnot confined to a printing couple of this precise type but is applicableto sheet fed machines and also to offset machines in which a blanketcylinder is interposed between the plate cylinder and impressioncylinder. The ink is supplied to the plate on the cylinder 1 by a pairof form rollers 4 and 4', which, in turn, are inked by a pair of trainsfrom an ink drum 11. Inasmuch'as the two trains supplying the formcylinders are similar and the elements are indicated by similarreference numerals, only the train supplying the form roller 4 requiresdescription.

Cooperating with the form roller 4 is a pair of rollers 5 and 6, theroller 5 being preferably carried in bearings which are pivotallyadjustable about the axis of roller 6, l

for adjustment along the are indicated. Rollers 5 and 6 are, in turn,supplied with ink through transfer rollers 7 and 8 from the drum orroller 9, which, in its turn, is supplied with ink from ink drum 11 bythe transfer roller 10. Rollers 4, 7, 8 and are surfaced with rubber orother soft material, as indicated, and will normally be driven only bytheir engagement with the cooperating elements and will be carried inadjustable bearings, as usual. The specific bearing adjustments forthese rollers fornrs no part of the present invention, and any suitableadjustable bearings may be used. Bearings such as shown in prior Harlessapplication Serial No. 189,699

filed October 12, 1950, now Patent No. 2,699,116 for Inking RollerMounting will be found suitable.

The cylinders 1, 2, 5, 6, 9 and 11 will, of course, be driven, as usual,and the cylinders 5, 6 and 9 (vibrators) will have the usual axialreciprocation, provided by any desired means. Huck Patent No. 2,300,549shows a suitable reciprocating arrangement for such elements, but any ofthe usual reciprocating arrangements may be employed.

The ink drum 11 is shown as supplied with ink by a ductor roller,swinging back and forth about a pivot point 13, between the drum 11 anda fountain roller 14 supplied with ink 15 from a fountain 16, thethickness of ink on the roller 14 being regulable by an adjustable blade17, as shown. The rotation of roller 14 may be intermittent orcontinuous, depending upon the arrangement of parts and operationdesired, and the drum 11 may be supplied with ink from an ink rail andink pumps instead of by an arrangement such as shown, where preferred.

In adjusting the mechanism for operation, the form roller 4 will bepositioned properly with reference to the cylinders 1 and 6, and thecylinder 5 may then be swung around the axis of cylinder 6 to bring itinto proper rela tion to the form roller 4 and fixed in this position.Transfer rollers 7, 8 and 10 may now be adjusted in proper relation totheir cooperating cylinders, completing the adjustments of the cylindersnecessary for printing.

The ink, whether supplied to drum 11 by a ductor roller or ink pumpswill, of course, require a working and distribution for producing therequired uniformity of film. The transfer rollers 10 and 10', cooperatewith the drum 11 for evening out the layer of ink thereon, and take inktherefrom and feed it to the trains feeding the two form rollers.axially in cooperation with transfer roller 10, and takes ink therefromand supplies it to the transfer rollers 7 and 8, the ink also beingworked at these points. The vibrators 5 and 6 work the ink axially andtake it from the transfer rollers 7 and 8 for supplying the form roller4. The action in the train supplying the form roller 4' is, of course,similar.

As will be apparent, the ink supplied to the form roller 4- is dividedinto two films on the transfer rollers 7 and 8, which films are broughtback into a single film on the form roller 4. This process ofsub-division and recombination of the ink film produces a much greateruniformity of ink film on the roller 4 than would be the case if the inksupplied thereto were merely worked without such division andrecombination.

The vibrators 5, 6 and 9 may reciprocate at any desired frequency and inany desired phase relationship for the particular, application involved,and, in particular, it will be normal practice to have the vibrators 5and 6 operating out of phase with each other. The vibrators in the othertrain supplying the form roller 4 may have similar phase relations amongthemselves and the phase relationship between the vibrators of the twotrains may also be selected and adjusted for maximum uniformity of inksupplied to the plate cylinder 1.

While applicable generally, the arrangement of the invention has beendeveloped primarily for use in hard packing letter press web printing,in which the usual practice has been to utilize two pairs of formrollers, each pair of which is supplied by a vibrator or other cylinder.In such arrangements, the form roller mounting with relation to theplate cylinder and cooperating vibrator or other supply cylinder isnecessarily such that the cylinder and roller engagement is notcapacitated to maintain the position of the form roller to avoidvibration and speed fluctuation thereof. While it has been usual in manyapplications to utilize only two form rollers The vibrator drum 9 worksthe ink' acne r L for inking the plate cylinder, similar conditions haveobtained in that this pair of form rollers has been inked by a commondrum and the relationship of the form rollers and cooperating elementshas been such as not to furnish the. required support for the formrollers. cording to the. present invention, it is preferred to arrangethe parts so that the. axes of the plate cylinder, form roller and avibrator cooperating with the form roller are substantially coplanar, orso that a plane through the axes of the. plate cylinder and form rollerpasses slightly between the axes of the vibrators cooperating with theform roller. The form roller 4 and vibrator roller 5 are shown as havingtheir axes substantially coplanar with the axis of the plate cylinder 1,while the form roller 4 is shown as having its axis slightly displacedfrom the plane containing the axes of the plate cylinder 1 and vibrator5', the displacement being toward the vibrator 6 so that support for theform roller is obtained from this element also. As will be apparent, thecylinder arrangement shown permits considerable variation in theplacement of parts with relation to each other, so that the lines ofcontact between the various elements may be arranged for obtaining theutmost smoothness in ink application while the cylinder supportingpositions are still maintained as desired. It is preferred to supportthe form roller 4 or 4- primarily by the adjustably mounted vibrator 5or 5' instead of the fixedly mounted vibrator 6 or 6, as thisarrangement permits the finest adjustment between form roller andvibrator for obtaining the required support.

As will now be apparent, when a gap or gutter between the plates passesa form roller 4 or 4, the vibration of the latter is very much reduceddue to its support in the radial direction by the vibrator 5 or 5'. Anytendency of the form roller to accelerate or decelerate at such time islikewise very much reduced by the engagement. of the form roller withthe two. vibrators rather than with only a single vibrator as is usualand by the substantially coplanar arrangement of the, form roller axiswith the printing cylinder axis and axis of one of the vibrators.

Tendency to print sparsely after heavy removal of ink by a solid area isalso very much reduced by the inking of the form roller at spaced pointsaround its periphery by the two vibrators. While it might seem,superficially, that the use of a larger number of form rollers would bemore effective in preventing such sparse printing, this is not actuallythe case, as, with form rollers of equal diameters, the relationship ofvarious areas of the printing plate with respect to the circumferentialareas of the form rollers will be similar. In the present arrangement,however, the relationship of the vibrators 5 and 6 to the form rollerwill not be the same with respect to the different areas of the platecylinder, as one area may primarily take ink supplied by one vibratorand another may take primarily ink supplied by the other.

The vibrators 5 and 6 may be of equal diameters, as shown, and theirarrangement with respect to the form roller and their axialreciprocation may readily be determined so as to obtain the best workingof the ink for producing uniform film on the form roller.

In the embodiment shown by way of example, the points of engagement ofthe vibrators with the form roller are spaced somewhat less than 90apart, and uniformity of working of the ink on the. form roller may beobtained by the reciprocation of the vibrators 5 and 6 out of phase byabout so that one vibrator is reciprocating at maximum speed while theother is reversing its direction of reciprocation. Under suchconditions, it will be apparent that the ink on the form roller 4 isworked axially over its entire area by either or both of the vibrators.

Where particular operating conditions and space limitations make itdesirable, the vibrators may be made of different diameters. Inparticular, the vibrator 5, furnishing the major support for the formroller, may be of larger diameter than the vibrator 6, permittinggreater support for the same without altering pressure per unit area orink film thickness.

What is claimed is:

1. A printing mechanism comprising, in combination, a printing cylinder,an ink drum, first and second form rollers for inking the printingcylinder, and for each of the said form rollers a train of rollers forsupplying ink from the ink drum to the form roller by two differentpaths, and comprising a pair of hard surfaced rollers spaced apart fromeach other and in contact with the form roller, and a pair of softsurfaced rollers, also spaced apart and respectively in contact with thesaid hard surfaced rollers, the various rollers on the said train beingarranged for applying all the ink supplied through the two differentpaths to the cylinder by means of the form roller.

2. A printing mechanism comprising, in combination, a printing cylinder,an ink drum, and first and second form rollers for inking the printingcylinder, and for each said form roller a transfer roller for taking inkfrom the ink drum, a train of rollers including rollers for conveyingink from the said transfer roller to the form roller by two differentpaths, the rollers in the two said different paths including a pair ofspaced apart hard surfaced rollers in contact, with the form roller, andalso spaced apart soft surfaced rollers in contact respectively with thehard surfaced rollers, whereby the ink taken from the ink drum andsupplied to the form roller is divided into two films and recombinedcompletely into a single. film on the form roller.

3. A printing mechanism comprising, in combination, a printing cylinder,a form roller for inking the same, a

' pair of vibrators in contact with the. form roller for sup-ReferencesCited in the file of this patent UNITED STATES PATENTS1,327,580 Wood Jan. 6', 1920 1,996,607 Barber Apr. 2, 19.35

2,004,801 Sheppard June 11, 1935 FOREIGN PATENTS 305,216 Great. BritainApr. 24, 1930 507,531 Germany Sept. 17, 1930

